GTV rattle at idle.

Tmode · #1 (**permalink**) 04-26-2008, 09:58 PM

My 1984 Alfetta GTV 2.0 has a rattle at idle which sounds like it's coming from the clutch / gearbox. The rattle goes away if I put my foot on the clutch and returns when I take my foot off. It only happens when the car is idling.
I've replaced the entire clutch assembly with a new one and also the driveshaft couplings and centre bearing without result.

The drive shaft is not hitting the exhaust or anything else.

I've run out of ideas. Can anyone help please.

Thanks!

alfettagtv2000 · #2 (**permalink**) 04-27-2008, 05:01 AM

have you checked the clutch release bearing for tightness on retainer hub?
(mine does that too)

**GreyGTV6** · #3 (**permalink**) 04-27-2008, 05:23 AM

Read Greg's article for a cure for this. It is possibly the splines at the rear of the drive shaft rattling on the shaft. A few ways to cure it is, either remove a bit of the clamp surface so the clamp is able to tighten back onto the input shaft, or flatten the splines a bit to eliminate the play. Greg's article covers it well, and explains it better than I am doing.

Steve.

**GreyGTV6** · #4 (**permalink**) 04-27-2008, 05:34 AM

The link for the article can be found here. A good site with lots of well written articles.

Alfa Romeo Guibo, DS, Clutch

Tmode · #5 (**permalink**) 04-27-2008, 09:26 PM

Thanks for the tips, I'll try them both.

car guy · #6 (**permalink**) 08-14-2008, 12:06 AM

Alfetta/milano/gtv6 clutch disc center splined cog is rotationally spring held. it is not fixed. When it becomes worn it produces excessive rotational end play which causes this rattle sound at idle at the rear. This type of clutch was introduced to improve gear selection from stop to first gear or reverse. A fixed cog clutch can be installed but gear selection will suffer. ciao!

**La Voce** · #7 (**permalink**) 08-15-2008, 06:21 PM

So the answer is, to stop the rattling noise, replace the clutch assembly?

fabcrab · #8 (**permalink**) 08-18-2008, 02:49 AM

I had the same problem on my sedan, i found the solution to be a tune up, after ballencing the carbs and setting the timing etc, the engine ran smoother and thus you didnt get the rattle down the back,

ToonRboy · #9 (**permalink**) 08-18-2008, 06:02 PM

Quote:

It is possibly the splines at the rear of the drive shaft rattling on the shaft. A few ways to cure it is, either remove a bit of the clamp surface so the clamp is able to tighten back onto the input shaft, or flatten the splines a bit to eliminate the play.

**La Voce** · #10 (**permalink**) 08-18-2008, 06:44 PM

sadly, my Alfetta is pinch-boltless. but what's the front of the driveshaft have to do with a rattling in the clutch area?

ToonRboy · #11 (**permalink**) 08-19-2008, 05:56 AM

Maybe nothing. Consider this: If the front connection of the driveshaft is loose, and all the mass is at the rear (where the clutch is), where do you think it's gonna wobble when the clutch is let out?

My issue sounds more like the middle, but happens as Tmode says, only when at idle. Goes away when clutch depressed or when in gear.

car guy · #12 (**permalink**) 08-19-2008, 01:32 PM

Because the heavy clutch assembly is located at the rear the rotational mass is absorbed by the clutch disc hub springs where as on a vehicle with the flywheel and clutch assembly mounted to the engine the rotational mass is absorbed by the crankshaft. FAB CRAB is right the smoother the engine runs the less wear on the clutch disc springs. If you install a fixed disc hub, the rattle is gone completly but gear change is stiffer because the drive line is tighter without the hub spring. I would install new clutch discs with springs, not rebuilt because of the wear that occurs on the inside of the clutch disc assembly that holds the spring assembly. I hope this helps.

ToonRboy · #13 (**permalink**) 08-19-2008, 03:56 PM

Good logic, but thread initiator said:

Quote:

I've replaced the entire clutch assembly with a new one and also the driveshaft couplings and centre bearing without result.

car guy · #14 (**permalink**) 08-19-2008, 05:34 PM

The best way to check if it is the clutch disc hub spring that is worn or defective is to lift the car off the ground, Release the hand brake, put the car in gear with the engine off. Turn the rear tire back and forth quickly and listen at the clutch assembly. If you hear the same rattle when the car is running, it is the clutch disc hub assembly that is worn or defective. A poor running engine will ruin the disc hub spring on these cars. If I had it my way I would have the clutch assembly at the engine not at the rear.

**La Voce** · #15 (**permalink**) 08-19-2008, 06:17 PM

Quote:

Originally Posted by ToonRboy

Good logic, but thread initiator said:

PO of my car also replaced the clutch assy & at least one giubo. There is no discernable rattle/vibration when in gear or on the move. This problem usually rears it's ugly head after someone has either replaced giubo's or the clutch & didn't follow proper procedure. It can also happen to a very tired or original driveshaft/clutch assy. I owned two Milano's (same drivetrain except isostatic shift mechanism) over a span of several years and never had this issue. When I get it resolved I'll come back and post. If Tmode doesn't beat me to it.